GoCoin enables you and your business to accept digital payments. If you are starting the integration process, you should read this document first.

Invoices and Bills

The GoCoin API revolves around 'Invoices.' An invoice is simply a commercial document that can be paid.

An *Invoice* is a request for payment that contains information necessary to remit payment to the issuer.

Any time a customer is paying you in Bitcoin, they will be paying a GoCoin invoice. Each invoice is assigned a single, never used payment address for the cryptocurrency the customer has chosen to pay with.

Invoices that have not been paid are said to be in an 'unpaid' state. An invoice can remain unpaid for 15 minutes. Rather, it has a 15 minute window in which payments are acceptable. This is how GoCoin is able to lock in our 'GoCoin spot rate' (our guaranteed exchange rate) for fiat currencies.

*Note: under certain circumstances, you can adjust the payment window using the API. Please contact us for more info

The semantic difference between an *invoice* and a *bill* is widely debated. However, within GoCoin, a 'Bill' is a special type of invoice.

A *Bill* is a request for payment that requires input before payment can be completed.

A Bill has not yet been assigned a price currency (currency it will be paid in), payment address, or a spot rate, and therefore must have additional data supplied before it can be paid. This also means that a Bill does not have a 15 minute payment window *UNTIL* that information is supplied.

The Hosted Gateway

GoCoin provides a hosted application that can display Invoices and Bills, so you do not have to render them inside your site or application.